Ohmic contacts for semiconductor devices and method for forming ohmic contacts
US4853346A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1987 |
| Grant date | Aug 1, 1989 |
| Priority date | — |
| Expiry date | Dec 31, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/62
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming an ohmic contact on a GaAs semiconductor material comprising depositing a non-uniform layer of Au onto the surface layer of the semiconductor material, depositing a multi-layer ohmic contact of AuGeNi onto the non-uniform layer and alloying the ohmic contact to the semiconductor material. The non-uniform Au layer may be deposited by backscattering Au during sputter cleaning of the semiconductor surface wherein the electrode is coated with Au. After alloying, the ohmic contact comprises a two layer structure having a high density of large area NiAs(Ge) grains contacting the semiconductor material as the first layer and an AuGa phase as the top layer. The ohmic contact has reduced contact resistance and exhibits a reduction in the spread of contact resistance after high temperature annealing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.